Conventionally, there is known a control device for a continuously variable transmission arranged to increase a belt capacity based on a release of an accelerator pedal (cf. for example, a patent document 1). When the brake pedal is depressed after the release of the accelerator pedal, the deficiency of the belt capacity with respect to the input torque from the driving wheel to the belt is prevented by the increase of the belt capacity, so as to prevent the belt slippage.
However, in a case where the conventional art is applied to a transmission provided with a stepwise variable transmission mechanism which has two or more gear stages, and which is disposed in series with the variator, an increase amount of the belt capacity is a fixed value, irrespective of the gear stage of the stepwise variable transmission mechanism. Accordingly, the belt capacity may be unnecessary increased, so that the fuel economy is deteriorated.